Phenotypic and epigenetic heterogeneity in FGFR2-fused glial and glioneuronal tumours.

Aims: FGFR-fused central nervous system (CNS) tumours are rare and are usually within the glioneuronal and neuronal tumours or the paediatric-type diffuse low-grade glioma spectrum. Among this spectrum, FGFR2 fusion has been documented in tumours classified by DNA-methylation profiling as polymorphous low-grade neuroepithelial tumours of the young (PLNTY), a recently described tumour type. However, FGFR2 fusions have also been reported in glioneuronal tumours, highlighting the overlapping diagnostic criteria and challenges.

Measuring the impact of treatment on memory functions in pediatric posterior fossa tumor survivors using diffusion tensor imaging.

Background And Purpose: The aim of the present prospective exploratory study was to investigate the long-term impact of treatment on brain structure integrity and memory functions in pediatric posterior fossa tumor (PFT) survivors using diffusion tensor imaging (DTI), to determine whether the latter could provide useful biomarkers of memory impairment.

Material And Methods: Sixty participants were included in this study, divided into three groups: 22 irradiated PFT, 17 non-irradiated PFT, and 21 healthy controls. All underwent memory tests and multimodal MRI, including a DTI sequence.

Brainstem toxicity after proton or photon therapy in children and young adults with localized intracranial ependymoma: A French retrospective study.

Background And Purpose: Ependymoma is the third most frequent childhood braintumor. Standard treatment is surgery followed by radiation therapy including proton therapy (PBT). Retrospective studies have reported higher rates of brainstem injury after PBT than after photon therapy (XRT).

The long-term impact of irradiation on functional connectivity in brain circuits involved in memory processes after pediatric posterior fossa tumor.

Purpose: Memory is one of the main specific cognitive domains impaired with attention and processing speed after a pediatric brain tumor. This work explored the long-term impact of radiotherapy in children with posterior fossa tumor (PFT) on brain connectivity in neural circuits involved in memory using resting-state functional magnetic resonance imaging (rs-fMRI).

Methods: A total of 20 irradiated and 15 non-irradiated PFT survivors, and 21 healthy controls, prospectively included in the IMPALA study (NCT04324450), performed memory tests assessing episodic, procedural, and working memories and were subjected to an rs-fMRI.

MRI-Based Deep Learning Tools for MGMT Promoter Methylation Detection: A Thorough Evaluation.

Glioblastoma is the most aggressive primary brain tumor, which almost systematically relapses despite surgery (when possible) followed by radio-chemotherapy temozolomide-based treatment. Upon relapse, one option for treatment is another chemotherapy, lomustine. The efficacy of these chemotherapy regimens depends on the methylation of a specific gene promoter known as MGMT, which is the main prognosis factor for glioblastoma.

CNS tumor with EP300::BCOR fusion: discussing its prevalence in adult population.

The Central Nervous System (CNS) tumor with BCOR internal tandem duplication (ITD) has recently been added as a novel embryonal histomolecular tumor type to the 2021 World Health Organization (WHO) Classification of CNS Tumors. In addition, other CNS tumors harboring a BCOR/BCORL1 fusion, which are defined by a distinct DNA-methylation profile, have been recently identified in the literature but clinical, radiological and histopathological data remain scarce. Herein, we present two adult cases of CNS tumors with EP300::BCOR fusion.

Pseudoprogression in GBM versus true progression in patients with glioblastoma: A multiapproach analysis.

Background And Purpose: To investigate the feasibility of using a multiapproach analysis combining clinical data, diffusion- and perfusion-weighted imaging, and 3D magnetic resonance spectroscopic imaging to distinguish true tumor progression (TP) from pseudoprogression (PSP) in patients with glioblastoma.

Materials And Methods: Progression was suspected within 6 months of radiotherapy in 46 of the 180 patients included in the Phase-III SpectroGlio trial (NCT01507506). Choline/creatine (Cho/Cr), choline/N-acetyl aspartate (Cho/NAA) and lactate/N-acetyl aspartate (Lac/NAA) ratios were extracted.

Assessment of the hypervascularized fraction of glioblastomas using a volume analysis of dynamic susceptibility contrast-enhanced MRI may help to identify pseudoprogression.

Purpose: Although perfusion magnetic resonance imaging (MRI) is widely used to identify pseudoprogression, this advanced technique lacks clinical reliability. Our aim was to develop a parameter assessing the hypervascularized fraction of glioblastomas based on volume analysis of dynamic susceptibility contrast-enhanced MRI and evaluate its performance in the diagnosis of pseudoprogression.

Methods: Patients with primary glioblastoma showing lesion progression on the first follow-up MRI after chemoradiotherapy were enrolled retrospectively.

Is systematic Gadolinium injection relevant during MRI follow-up for non-functioning pituitary macroadenomas?

Objective: To compare the performance of coronal contrast-enhanced T1-weighted (ceT1-w) and T2-weighted (T2-w) sequences for diagnosing progression during the MRI follow-up of Non-Functioning Pituitary MacroAdenomas (NFPMAs).

Patients And Methods: 106 patients, who had at least two MRIs for the follow-up of NFPMA, were enrolled retrospectively. The largest adenoma diameter was measured on coronal ceT1-w sequences and separately on T2-w sequences for all follow-up MRIs.

Pseudoprogression in Glioblastoma: Role of Metabolic and Functional MRI-Systematic Review.

Background: Glioblastoma is the most frequent malignant primitive brain tumor in adults. The treatment includes surgery, radiotherapy, and chemotherapy. During follow-up, combined chemoradiotherapy can induce treatment-related changes mimicking tumor progression on medical imaging, such as pseudoprogression (PsP).

A prospective behavioral and imaging study exploring the impact on long-term memory of radiotherapy delivered for a brain tumor in childhood and adolescence.

Background: Posterior fossa tumors represent two thirds of brain tumors in children. Although progress in treatment has improved survival rates over the past few years, long-term memory impairments in survivors are frequent and have an impact on academic achievement. The hippocampi, cerebellum and cerebellar-cortical networks play a role in several memory systems.

Leptomeningeal enhancement on post-contrast FLAIR images for early diagnosis of Susac syndrome.

Background: Leptomeningeal enhancement (LME) is a key feature of Susac syndrome (SuS) but is only occasionally depicted on post-contrast T1-weighted images (T1-WI).

Objective: As post-contrast fluid-attenuated inversion recovery (FLAIR) may be more sensitive, our aim was to assess LME in SuS on this sequence.

Methods: From 2010 to 2020, 20 patients with definite SuS diagnosis were retrospectively enrolled in this multicentre study.

Absence of susceptibility vessel sign is associated with aspiration-resistant fibrin/platelet-rich thrombi.

Background: The composition of the thrombus influences its retrievability by mechanical thrombectomy.

Purpose: Our study aimed to report on thrombi resistant to aspiration, regarding susceptibility vessel sign and histologic composition.

Methods: This observational study was based on a prospective database of acute anterior circulation ischemic strokes treated by mechanical thrombectomy.

Impact on survival of early tumor growth between surgery and radiotherapy in patients with de novo glioblastoma.

Purpose: Systematic pre-radiotherapy MRI in patients with newly resected glioblastoma (OMS 2016) sometimes reveals tumor growth in the period between surgery and radiotherapy. We evaluated the relation between early tumor growth and overall survival (OS) with the aim of finding predictors of regrowth.

Methods: Seventy-five patients from 25 to 84 years old (Median age 62 years) with preoperative, immediate postoperative, and preradiotherapy MRI were included.

Predictive Value of Susceptibility Vessel Sign for Arterial Recanalization and Clinical Improvement in Ischemic Stroke.

Background and Purpose- Our goal was to evaluate whether the presence of a low signal intensity known as susceptibility vessel sign (SVS) on T2*-gradient echo imaging sequence was predictive of arterial recanalization and the early clinical improvement after mechanical thrombectomy. Methods- This observational study was based on a prospective database of acute ischemic strokes treated by mechanical thrombectomy. Inclusion criteria were patients with acute anterior ischemic stroke, diagnosed by magnetic resonance imaging, including a T2*-gradient echo imaging sequence, and treated by mechanical thrombectomy.